Head-mounted displays and other wearable displays have emerged in conjunction with wearable computing devices. Head-mounted and certain other wearable displays create the illusion of an image floating in free space in front of the user through projection of a visual user interface onto, for example, a transparent surface mounted on a pair of eyeglasses. The projected visual interface is also typically transparent so that the interface does not block out existing light behind it. Accordingly, the projected visual interface appears to be overlain or otherwise viewed “on top of” the user's field of view. The visual user interface is generally always projected to the same portion of the display.